Abstract: An X-radiation protection circuit in a television receiver is responsive to both high voltage and high beam current conditions. A first detector is interconnected with an electron beam power source and monitors the beam current therefrom. The first detector produces a first voltage proportional in magnitude to the electron beam current. A second detector monitors a high voltage transformer that produces a potential for operating on the electron beam and the second detector produces a second voltage that is proportional in magnitude to the high voltage potential. A monitoring circuit constantly monitors both the first and second voltages and produces a trigger signal whenever the additive sum of the first and second voltages exceeds a selected magnitude. In this manner, a trigger signal indicates an excessively high combination of electron beam current and high voltage.

Abstract: For use in an activated sludge process, dual-baffle aerators for both vertically mounted surface aerators and static mixer-aerators are disclosed. These devices substantially prevent back-mixing of freshly aerated liquor into aerator intakes and provide directional propulsion. By connecting two or more such devices to form a barrier across the channel of an oxidation ditch, homogeneous aeration is provided to the mixed liquor. Barriered pump/aerator assemblies utilizing directional mix jet aerators (eddy jet) are also described. These devices can also be combined with dual-baffle aerators to furnish both propulsion and a selected degree of homogeneous aeration in a barrier oxidation ditch. An adjustably apertured barriered pump assembly is additionally disclosed for providing a selected balance between homogeneous aeration and/or mixing and heterogeneous aeration and/or mixing.

Abstract: An apparatus for aerating waste water comprising a surface aerator adapted to rotate about a vertical axis. A cap is disposed over the aerator and is modified to improve the operation of the apparatus. The waste water flows in a closed circuit and a partition is provided separating the parts of the circuit lying upstream and downstream of an aeration zone. The surface aerator is arranged in an aeration zone in the neighborhood of an end of the partition.

Abstract: The invention relates to a liquid atomizer having a liquid atomizing rotor rotatable about an axis, and designed to feed a liquid into its inlet, along a liquid flow surface of the rotor and through its outlet as an atomized spray. The liquid flow surface is formed by a bent sheet member, fluted or zig-zag in formation, forming a closed figure surrounding the axis, and two generally symmetrically formed sheet portions, and doubler seams on diametrically opposite sides of the sheet portions for counterbalancing during rotor rotation about the axis.

Abstract: A flotation platform supports a mast assembly through which a drive shaft extends having a wind driven turbine on the upper end and a propeller on the lower end situated below the water surface. The propeller is rotated by the wind turbine and causes localized water circulation in the body of water in which the mill is situated thus aerating and mixing the water in the summer and also maintaining an ice free area around the mill in winter.

Abstract: A bioreactor for cell culture medium is provided including a flask for holding the culture medium, a screen at or just below the surface of the culture medium, a mover for the screen to cause it to move generally parallel to the surface of the culture medium, and an integral or separate impeller to cause circulation of the culture medium to the surface of the liquid culture medium. The screen is preferably on a float, and is connected to be driven at different levels of the liquid in the flask.

Abstract: An apparatus for humidifying and purifying the air of a room. The apparatus has a water supply tank with a cover in which is mounted a motor. Disposed on the motor shaft is a fan wheel for generating a flow of air through the housing, a fan wheel for cooling the motor, and a pump tube. When the pump tube is rotated, it delivers a stream of liquid that leaves the pump tube as a free, sheet-like swirl of water through which the air flow is positively guided. Consequently, the air flowing through the swirl of water is purified and humidified.

Abstract: A method and apparatus for oxygenating water in an aquaculture system without adding nitrogen or other possibly harmful gases. A columnar housing floats in the aquaculture pond on a float ring with a submersible pump immersed in the pond. The pump draws in water and pumps it to the top of an oxygenation chamber which is packed with a surface expansion medium. The oxygenation chamber is filled with oxygen which is transferred to the water falling through the chamber. The oxygenated water is returned to the pond through outlet ports at the bottom of the oxygenation chamber. A cover on the column can be removed at times to allow infiltration of air for aeration of the water.

Abstract: An apparatus for aerating waste water comprising a surface aerator adapted to rotate about a vertical axis. A cap is disposed over the aerator, said cap being modified in several ways to improve the operation of the apparatus. In one embodiment a gas outlet opening with an exhauster is provided in a wall of the cap. Further circumferential spaced baffles may be disposed inside the cap. The cap may have a side wall with a lower edge extending vertically downwardly or inwardly. Other embodiments of the cap are specifically adapted for use in an installation for treating waste water, in which the apparatus serves also for bringing the liquid into circulation.

Abstract: An aerator for oxygenating the water in a pond or the like is disclosed, the aerator having a housing with a floatation collar therearound and a motor disposed in a vertically adjustable bracket mounted in the housing. A propeller is secured to the motor shaft and the bracket is adjusted so as to dispose most of the propeller above the surface of the water to create a flow of water from lower levels of the pond through the housing, during operation of the aerator. The propeller is designed to increase agitation, having straightened blade ends and notches cut in the blades, the agitation and spray serving to oxygenate the water and to allow harmful gases to escape to the atmosphere.

Abstract: A portable humidifier for insertion into a receptacle for water, including an outer housing which has outlet openings formed therein, a support structure for holding the housing in depending relation within the liquid receptacle, and a driven fan positioned in the housing and arranged to draw moisture-laden air up through the housing and out the outlet passages. An inner housing is slidably received within the outer housing in telescoping relation. A secondary, non-driven fan is positioned within the inner housing for rotation therein and is arranged to disperse water droplets into the airflow created by operation of the driven fan. An air inlet means is arranged to direct air through the inner housing to be propelled with the water droplets upwardly into the outer housing for discharge through the outlet openings. The device is foldable to a compact structure making it convenient to be carried in a suitcase or the like.

Abstract: A motor supported by a float drives an impeller having eight symmetrically oriented vertical vanes radially attached to a cylindrical hub submerged below the surface of a wastewater lagoon. The size, position, and rotation rate of the impeller are selected to centrifugally expel wastewater between the vanes and cause a vacuum therebetween. An air vortex is produced between the lagoon surface and the top of the impeller, drawing air along the shaft of the impeller into the vacuum region. The incoming air and water is "sheared" by the vanes, causing great turbulence producing a mixture of water with millions of minute air bubbles entrained which is centrifugally thrown outward by the impeller, producing a deep, large radius zone of influence. The minute bubbles remain in the wastewater for a relatively long period of time, greatly improving dissolved oxygen levels. An air screw device disposed in the air vortex region increases the efficiency of the device.

Abstract: A surface-aeration rotor is provided with a carrier-part connected to a vertical drive-shaft. Secured adjustably to the carrier-part are several liquid-conveying units each consisting of a scoop and two flow-guiding walls. In order to improve the oxygen-input performance per kilowatt of rotor-drive power, the liquid-conveying units are designed in such a manner that the scoops are disposed in a plane which is twisted and which is curved in the direciton of rotation of the rotor, whereby the jets of liquid emerge from the rotor standing on edge.

Abstract: A portable electric humidifier uses a flexible, disposable bag as a container for water, to provide a compact, collapsible, and easily portable system. A humidifier head contains a motor and an air humidifying apparatus such as a spinning disk and conical shaft. The head is supported on folding legs. The flexible bag is supported by and hangs beneath the humidifier head. The conical shaft extends downwardly from the spinning disk and draws water from the bag and conveys it to the disk, from which it is dispersed in an air stream into a room. The shaft in one embodiment telescopes, to occupy a minimum vertical distance for storage within the height of the folded legs, and in another embodiment is removable for storage. The flexible bag container is inexpensive and may be discarded after use at one location, prior to packing for further travel. Thus, the humidifier provides overnight humidification for a hotel room or the like, while being conveniently packable for transportation in any small suitcase.

Abstract: The invention comprises a reservoir for containing water, and a bubble tank which holds water for forming bubbles. A bubble generator, rotatably supported and positioned in contact with the tank water, mingles water and atmospheric air such that copious bubbles are formed when the generator is rotated. The water in the bubble tank is maintained at a substantially constant level by a feedback system which draws replacement water from the reservoir as the tank water is evaporated. A blower moves atmospheric air to the erupting bubbles to hasten evaporation and propels the moistened air into the local environment.

Abstract: Gases that are to be scrubbed, particularly flue gases, pass through an inlet line (14) into a processing area (9) wherein the gases are exposed to the effects of a scrubbing agent that is contained in a bath (4). To this end, the liquid is sprayed by means of a rotating disc arrangement (17), the discs of which are coated--preferably through a hollow shaft (18)--with a layer of the scrubbing agent, this coating then being separated from the rotating discs as a result of centrifugal forces, with the attendant formation of an annular spray zone. The gas scrubber can trap sulfur dioxide that is contained in the flue gases. To this end, water is used as the scrubbing agent, and sodium carbonate (soda) is added to this.

Abstract: A floating platform structure mounted on ballast tanks disposed in a tank having the liquid to be mixed and/or aerated by an impeller carried by the platform. Guide members on the structure have longitudinally spaced sets of rollers slidably engaging upstanding posts in the tank and restrain the platform against rocking or horizontal movement due to wind or wave action, while allowing the platform to rise and fall with changes in the level of liquid in the tank.

Abstract: A fuel vapor generator capable of being incorporated within a carburetor having a housing defining a chamber at the bottom thereof. An input line is attached to the lower portion of the housing for introducing a liquid fuel into the chamber and a return line is also attached to the lower portion of the housing for removing any excess liquid from the chamber and returning the excess liquid to the chamber. Located within the chamber is a level regulating system which, by being operably connected to both the inlet and removal lines is capable of regulating the liquid level within the chamber. In addition, an atomizer is located within the chamber in order to spray the liquid fuel in mist form into the upper portion of the housing for vaporization thereof prior to introduction into the Venturi tube of a carburetor.

Abstract: A dual baffle pump/aerator assembly comprising a concave intake baffle which is disposed upon the floor of an endless channel of an oxidation ditch to intercept the flow of mixed liquor within the channel. A horizontal barrier having aeration means associated therewith is disposed above and attached to the intake baffle. A concave discharge baffle is disposed above and attached to the horizontal barrier.

Abstract: Apparatus for mixing air with liquid, an aerator or oxygenator, comprises a motor or other power drive generally mounted in vertical position on a floating or a fixed structure, the motor having a shaft extending downwards through an opening in the center area of the float or fixed structure and bearing on its lower part a screw pump portion located in a cylindrical volute section just below the water level. When the apparatus is operating, the waste-water is sucked by means of the screw pump from the bottom of the body of liquid at which the apparatus is positioned and is pushed upwards in order to be diffused by means of a centrifugal impeller having outwardly curved blades, at least one of which extends downward to merge with a spiral shaped portion of a blade on the screw pump.

Abstract: A portable electric humidifier uses a flexible, disposable bag as a container for water, to provide a compact, collapsible, and easily portable system. A humidifier head contains a motor and an air humidifying apparatus such as a spinning disk and conical shaft. The head is supported on folding legs. The flexible bag is attached to and hangs beneath the humidifier head. The conical shaft extends downwardly from the spinning disk and draws water from the bag and conveys it to the disk, from which it is dispersed in an air stream into a room. The shaft telescopes, to occupy a minimum vertical distance for storage within the height of the collapsed legs. The flexible bag container is inexpensive and may be discarded after use at one location, prior to packing for further travel. Thus, the humidifier provides overnight humidification for a hotel room or the like, while being conveniently packable for transportation in any small suitcase.

Abstract: The invention relates to an immersible aerator and/or mixer apparatus to be lowered onto the bottom of a basin or tank containing liquid, often also solid substances, and particularly the invention relates to the supporting structures of the said apparatus as well as to the devices for protecting the motor and power transmission chambers of the said aerator and/or mixer apparatus from the liquid contained in the said vessel.

Abstract: In aerobic wastewater treatment systems, such as sewage treatment, liquid in a channel spanned by a liquid-tight barrier is moved past the barrier by a liquid-gas contact pump, thus dissolving a gas in the liquid and creating a differential head that provides flow energy for moving the liquid in plug-type flow through the channel, which is preferably a continuous-flow pipeline or a circuit-flow oxidation ditch, without energy-wasteful vertical circulation. The barrier further provides a structure for mounting submerged static aerators or a draft tube, in combination with a surface aerator, such as a submerged turbine or surface-disposed impeller aerator, as the liquid-gas contact pump. The barrier is disposed at sufficient depth, when combined with static aerators or when telescopically attached to the draft tube of a floating surface aerator, to enable the liquid level to be selectively varied so that flow equalization to an oxidation ditch and wastewater storage therewithin are provided.

Abstract: A gas-liquid contacting device is disclosed which comprises a frame, a driving means mounted to the frame, a vertical rotating shaft rotatably mounted to the frame and adapted to be driven by the driving means, and a rotor secured to the lower end of the vertical rotating shaft, the rotor being substantially a hollow body of rotation e.g. a hollow inverted cone with a center line coaxial to the axis of the rotating shaft. The rotor is adapted to be immersed partly or entirely into the liquid to be mixed with a gas, e.g. air.

Abstract: An integral clarifier is provided that operates without a pump by deriving the clarifier feed stream and its accompanying pump head from the flow being pumped through the draft tube of a draft tube circulator/aerator assembly in a complete mix system or in a basin oxidation ditch. The clarifier feed stream is delivered to the clarifier with this pump head substantially intact to create a differential hydraulic head between the surface of the clarified liquor within the clarifier and the surface of the mixed liquor within the complete mix tank or within the endless channel of the barrier oxidation ditch. The clarifier may be located in any suitable place but is preferably alongside the complete mix tank or alongside the discharge channel of the barrier oxidation ditch, within the discharge channel so that its upstream side forms the barrier, or surrounded by the endless channel, particularly if the clarifier and the ditch are circular in shape.

Abstract: A self-propelled aeration device comprising a jet-aerator mounted on floats and connected by a hinged arm to a central pile for enabling the said aerator to rotate around the pile thus mixing and aerating both the large surface and great depth of a reservoir. As the jet-aerator a weir or orifice, preferably tooth-shaped orifice, are employed. In order to reduce the obstruction of jets and the wind resistance most of the elements of the floating structure are combined in a central box. The said box is self-supporting on water so that only small balancing floats are needed in addition to the central box in order to provide the stability of the floating structure. The device has provisions for preventing icing and clogging.

Abstract: Apparatus for mixing air with liquid (aerator or oxygenator) comprises a motor or other power drive generally mounted in vertical position on a float or a fixed structure, the motor having a shaft extending downwards through an opening in the center area of the float or fixed structure and bearing on its lower part a propeller located in a cylindrical volute section just underneath the waterlevel. When the apparatus is operating, the waste-water is sucked by means of the propeller from the bottom of the body of liquid on which the apparatus is floating and pushed upwards in order to be diffused by means of a rotating diffusion head in the shape of a paddle-wheel. This feature increases efficiency of the installation, allowing the velocity of the fluid leaving the propeller to be kept as low as possible and the dimensions of intake volute and propeller to be increased.

Abstract: The rotary surface aeration device used to rotate and aerate sewage is provided with a carrying part connected to a vertically running drive axle. A plurality of liquid transporting units also fastened to the carrying part.In order to improve the oxygen input, the liquid transporting units, which are adjacent to each other viewed in the circumferential direction of the rotary aerating device, have different jet exiting speeds. This is achieved by giving the scoop outlet edges of these liquid transporting units, which are adjacent to each other, a different distance (d, d') from the drive axle of the rotary aeration device. The liquid transporting units are arranged and constructed in such a way that the liquid jets of at least two liquid transporting units, which are adjacent viewed in the circumferential direction of the rotary aeration device, exiting from said units during the operation of the rotary aeration device strike each other before reentering into the liquid to be aerated.

Abstract: A hydraulically powered mixing aerator rides on an upright beam member for submersion in a body of water such as an equalization basin, oxidation ditch or sludge holding tank used in sewage treatment plants. The aerator employs a submersible, hydraulically powered mixing motor driving a propeller which is mounted on the beam member by a slidable bracket for height adjustment. The beam member is swingably supported to allow adjustment of the vertical plane angle. Because the beam member is also mounted for rotation, substantially any attitude or position of the mixer can be selected for creating an efficient flow pattern within the body of water. The speed at which the propeller is rotated, and therefore, the rate at which the water is circulated and aerated, is selectively adjustable. The hydraulically driven motor provides for a low speed and high torque rotation of the propeller without the use of a reduction gear.

Abstract: In a process for mixing a gas and a liquid in an apparatus having an axial flow down-pumping impeller located in a draft tube and preceded by a first baffle wherein a vortex and turbulence are created and gas is drawn into the vortex, the improvement comprising providing liquid velocity of at least one foot per second, increasing the turbulence, providing a second baffle below the impeller, and a high shear zone between impeller and the second baffle.

Abstract: A mixer for mixing a body of receiving liquid with solids, liquids or gases introduced therein. The mixer includes a rotatable shaft, a thin disk-like member mounted for rotation on the shaft, and at least one thin annular ring mounted on the disk-like member spaced from, parallel to and concentric with it. The flow of liquid perpendicular to the annular ring through the inner opening thereof, when the mixer is immersed and rotating in the body of receiving liquid, is unimpeded by any structural member. The annular ring may be mounted on either side of the disk, and a plurality of annular rings may be employed. The annular ring or rings may be mounted on the disk-like member by at least three elongated support posts spaced equally around the outer perimeter of the disk, the transverse cross-section of each post being curvilinear, preferably circular, in shape. The mixer is disclosed for use in a tank.

Abstract: Methods are provided for converting both plug flow and complete mix basins of the prior art into barrier oxidation ditches. Circulator/aerators are described that can be prefabricated and dropped onto the floor of an existing basin so that, in combination with at least one partition, if needed, an endless channel is created with minimum disruption of the activated sludge process.

Abstract: An improved humidifier having a permanant motor housing mounted above a reservoir. A disposable aerosol generator is releasably attached to the motor housing and the reservoir is lined with a disposable liner. The aerosol generator and liner are replaceable.

Abstract: Methods are provided for converting both plug flow and complete mix basins of the prior art into barrier oxidation ditches. Circulator/aerators are described that can be prefabricated and dropped onto the floor of an existing basin so that, in combination with at least one partition, if needed, an endless channel is created with minimum disruption of the activated sludge process.

Abstract: The invention provides an aerator device for dispensing liquid in a gas phase by producing an upwardly-directed spray of the liquid from a tank. The device, which is intended to be submerged in a tank, comprises a motor-pump unit in the vicinity of the tank floor and a primary flared tube and a secondary flared tube coaxial therewith. The secondary flared tube is connected to a delivery nozzle by an intermediate duct, and the delivery nozzle is surmounted by an adjustable needle. The buoyancy of the whole assembly is ensured by a set of variably ballasted buoys which pivot at the end of support arms, and by an upper buoy concentric with the nozzle.

Abstract: A floating aerator for a body of water includes a motor and deflector cone assembly whose connecting rods are adjustably secured to angle support feet which are stably seated in recesses formed in the top of a float body. The device is efficient and economical to manufacture.

Abstract: Apparatus for contacting a liquid, in a tank containing a body of same, with a gas from a gas space overlying the body of liquid. A generally tubular draft member is disposed in the tank, having a cylindrical main body portion and an outwardly flared conical inlet upper section forming a liquid inlet at its upper end. Enclosing walls of the conical inlet section form an angle with the draft member central axis of from 5.degree. to 35.degree. and the conical inlet section has a vertical height of from 0.25 to 1.25 times diameter of the draft member. A rotatable axial pumping impeller is provided in the draft member for rotational vortex entrainment of gas in downwardly flowing liquid pumped through the draft member. Baffle means are positioned in the conical inlet section of the draft member to prevent bulk rotation of liquid in the tank during rotation of the impeller.

Abstract: A surface aerating rotor has an intake zone for circulating and aerating a liquid, and includes a supporting assembly, a driving shaft connected to the supporting assembly, fixed flow guidance devices disposed in the intake zone of the rotor, and a plurality of fluid throughput units. Each fluid throughput unit has a discharge opening, and includes a vane which has an adjustable discharge angle with respect to the radial direction, and at least one flow guide wall. At least some of the fluid throughput units include an extension member downstream of the discharge opening, a flow guide profile on the extension member, and a baffle downstream of the flow guide profile. Connecting pins join the fluid throughput units to the supporting assembly, for adjustment of the vane discharge angle within a predetermined range.

Abstract: A surface aerator is provided which includes a float, a throat or draft tube supported by the float and forming a float unit therewith, a power module including a motor and a propeller which is driven by the motor and is disposed within the throat of the float unit, and a mounting ring construction for mounting the power module in spaced relationship above the float unit. The mounting ring construction includes upper and lower rings joined together by a series of upstanding rods. The upper ring is bolted to the power module by bolts which extend into the rods and the lower ring is bolted to the float unit by bolts which extend through circumferentially spaced apertures in the lower ring.

Abstract: An absorber for increasing the concentration of oxygen in a solution has a pressure chamber therein which receives oxygen under pressure as well as a liquid to be oxygenated within an upper portion thereof. A shaft on which a turbine blade agitator is mounted is located in the upper portion of the chamber. The shaft is driven rotationally by a motor through a rotary seal in the pressure chamber cover. A baffle plate is mounted within the pressure chamber to define a lower portion therebeneath, which is in communication with the upper portion, but isolated from the agitation in the upper portion. The oxygen-liquid solution which drains into the lower portion is subsaturated and relatively quiescent, so that large oxygen bubbles therein disengage and rise into the upper portion, and entrained small bubbles therein dissolve in the subsaturated oxygen-liquid solution.

Abstract: A foam breaker for a fermentation reactor has one or more curved rods, preferably hollow rods with open ends (tubes), and an arrangement for so mounting these on the rotor of the reactor that they rotate with the rotor. The rods or the tubes have leading ends or inlets respectively which scoop up liquid of the liquid phase contained in the reactor, and opposite closed ends or outlets respectively at or through which this liquid is slung away or expelled in form of jets which pass through and destroy a layer of foam that forms above the liquid phase in the reactor.

Abstract: Self-contained treatment apparatus for a body of water includes a mounting assembly having flotation elements for fixedly supporting a circulation or agitation device below the surface of the water and driving or motor mechanism above the water surface. Actuation of the motor mechanism operates the circulation or agitation device such that naturally occurring oxygen-saturated water near the surface is drawn downwardly and mixed with the lower oxygen deficient reaches of the body of water and effecting a net increase in dissolved oxygen content. Optionally, actuation of the motor mechanism operates a bubble generator adjacent the water surface so that the air bubbles generated are drawn down with the oxygen-saturated surface water, where oxygen from the bubbles dissolves into the surrounding oxygen-deficient water, thus accelerating the improvement in dissolved oxygen content.

Abstract: A modified internal combustion engine useful as a power plant in automotive vehicles is operated on an admixture of air and fuel vapor. An apparatus is disclosed for generating the fuel vapor from a volatile normally liquid fuel of the type useful in operating a conventional internal combustion engine having a prior art carburetor. Apparatus is also disclosed for safely handling and controlling the fuel vapor thus generated, and utilizing the same in the operation of the internal combustion engine. In a further aspect, a novel method is provided for generating vapor of a volatile liquid fuel and operating an internal combustion engine therewith. The method is also useful in modifying a conventional internal combustion engine including a prior art carburetor. The resultant modified internal combustion engine operates more efficiently and with lower exhaust emissions.

Abstract: A method of and an apparatus for aerating and circulating a liquid in a vessel comprising utilizing a surface aerator and a bottom mixing rotor mounted on a hollow common shaft. The rotor entrains liquid and air into the hollow center of the common shaft from the liquid surface region and affects a downward two-phase flow in the hollow center. The gas-liquid mixture is subsequently injected into the liquid body through the channels of the rotor which communicate with the hollow center of the shaft. The discharged jet streams disperse the entrained gas bubbles throughout the liquid body and provide turbulent mixing in the bottom section of the vessel. The present invention not only provides sufficient bottom mixing but also enhances the mass transfer efficiency of the surface aeration by enriching the gas content in the surface layer of the liquid.

Abstract: Evaporation air humidifier having a pump, a motor for driving the pump having a shaft extending through a support plate into a water supply container, the shaft carrying a pump wheel or vanes disposed in a lower pot-shaped pump housing formed with a suction opening and a connecting piece for connecting a pressure line thereto, including a longitudinally divided support pipe surrounding the motor shaft and connecting the pump housing to the support plate, the support pipe being formed of two longitudinal shells having jointing surfaces formed with a wedge-shaped bevel at respective ends thereof extending into an opening formed in the support plate, at least one of the shells being suspended under clamping action from the support plate in vicinity of the opening formed therein, and connecting means for mechanically holding the shells and the pot-shaped pump housing together.

Abstract: This flow-control apparatus for an oxidation ditch comprises a barrier which divides a channel of an oxidation ditch into an intake channel and a discharge channel, at least one submerged turbine which pumps mixed liquor from the intake channel, and at least one discharge duct which connects each turbine to the discharge channel and passes beneath the barrier. Compressed air is supplied to each turbine and/or to each discharge duct. Activated sludge is fed to the anoxic portion of the ditch and/or to each turbine which provides complete mix and propels the mixed liquor in plug-type flow through the channels of the oxidation ditch. By selectively and independently controlling turbine speed and amount and/or feed location of compressed air, the timed aerobic/anoxic ratio for the ditch can be controlled in accordance with independent parameters, such as seasonal temperatures.

Abstract: Several forms of surface impeller for aeration of liquids are disclosed. All of the forms are of the shrouded or closed turbine type. In one form, the impeller has a large-diameter flat steel horizontal upper disc adapted to be secured to the lower end of a vertically disposed rotatable drive shaft. Secured, as by welding, to the undersurface of the upper disc are a plurality, such as six or eight or other number, of vertical blades at uniform spacing. Each blade is curved in a retreating or backward direction relative to the direction of rotation of the impeller. Each blade has a long or deep vertical inner edge located forward of the center axis of rotation. The lower edge of each blade is inclined upwardly toward a relatively short or shallow vertical outer edge located near the outer periphery of the upper disc. The horizontal innermost portion of the otherwise inclined bottom edge of each blade is welded to a small lower tie plate.

Abstract: An aerator apparatus for use in waste treatment plants and the like for imparting oxygen to the waste water forced through the apparatus by an axial flow impeller. The entire apparatus may be submerged, resting on the bottom of the body of water and has an intake area for directing water from the bottom of the body of water through the apparatus. The water is forced into a discharge chamber where it is aerated and agitated by a compressed oxidizing gas, such as air, through an array of ports surrounding the discharge chamber. From the discharge chamber the aerated water is directed out of the apparatus on a generally horizontal plane into the surrounding body of water. In one embodiment, the flow of water may be drawn from a certain direction and discharged in the same or opposite direction, as desired, to maintain a flow or current pattern in conjunction with a plurality of like aerators.

Abstract: A system for performing an oxygenation process within a body of sewage at atmospheric pressure includes an oxygen absorber coupled to an oxygen supply at superatmospheric pressure. A storage vessel has an elongate chamber therein which is oriented vertically in the system. Pipes and valves are coupled to the upper and lower ends of the chamber so that the chamber is alternately communicated with the oxygen absorber and the body of sewage, thereby providing alternate high pressure and low pressure half cycles respectively. Initially, oxygenated liquor at superatmospheric pressure is in the oxygen absorber and the elongate chamber is filled with a quantity of low oxygen content liquor at atmospheric pressure. The valves are then operated during the high pressure half cycle to admit oxygenated liquor into the elongate chamber through the lower end and to simultaneously expel liquor and undissolved oxygen from the upper end into the oxygen absorber.

Abstract: In a process for mixing a gas and a liquid in an apparatus having an axial flow down-pumping impeller located in a draft tube and preceded by a first baffle wherein a vortex and turbulence are created and gas is drawn into the vortex, the improvement comprising providing liquid velocity of at least one foot per second, increasing the turbulence, providing a second baffle below the impeller, and a high shear zone between impeller and the second baffle.